Simulations are useful in modeling the flow of transactions through processes, such as in the field of sales process engineering, to study and improve the flow of customer orders through various stages of completion (e.g., from an initial proposal for providing goods/services through order acceptance and installation). Such simulations can help predict the impact of how improvements in methods might impact variability, cost, labor time, and the quantity of transactions at various stages in the process. A full-featured computerized process simulator can be used to depict such models, as can simpler educational demonstrations using spreadsheet software.